Printing plate delaminating apparatus



Jan. 23, 1968 G GOCCE ET AL 3,364,556

PRINTING PLATE DELAMINATING APPARATUS Filed July ll, 1966 f/o Fl UnitedStates Patent O 3,364,556 PRINTING PLATE DELAMINATING APPARATUS Guy J.Cocce, Ansonia, and Emil Ivan, Derby, Conn., assignors to CharltonPress, Incorporated, Derby, Conn., a corporation of Connecticut FiledJuly 11, 1966, Ser. No. 564,061 Claims. (Cl. 29-239) The presentinvention relates to printing plates and, more particularly, toapparatus for delaminating a printing plate and a backing plate.

It is well known in the prior art to separate a printing plate from asaddle or backing plate by heating the plates to soften or destroy theadhesive connecting the plates and then manually driving a sharp tooltherebetween to separate them so that the components may be remelted orreused. This process is slow and expensive as it requires relativelylarge amounts of manual labor and often results in damage to the parts.

It is an object of the present invention to provide a novel andeffective power driven apparatus for separating a printing plate from abacking plate.

It is also an object to provide such a delaminating apparatus thatseparates a printing plate from a backing plate rapidly and withoutdamage to these parts and which is relatively simple and rugged inconstruction.

Still another object is to provide such apparatus which is adapted totake printing plate assemblies of varying size and edge configuration.

Other objects and advantages will be readily apparent from the followingdetailed description and attached drawings wherein:

FIGURE l is a perspective View of the printing plate delaminatingapparatus of this invention with portions broken away to illustrate theoperating parts;

FIGURE 2 is a cross-sectional view of the delaminating apparatus ofFIGURE l;

FIGURE 3 is a fragmentary sectional View in elevation of thedelaminating apparatus illustrating the operating parts in the startingposition;

FIGURE 4 is a view similar to FIGURE 3 with the operating partsillustrated in the final position; and

FIGURE 5 is an exploded view of the printing plate assembly formed bythe printing plate, adhesive, and mounting plate or saddle and shown inFIGURES 1 4.

It has now been found that the foregoing objects and other advantagescan be readily attained in apparatus for delaminating a printing plateassembly having a housing with a plate support thereon having means forsupporting in a position normal thereto one end portion of a printingplate assembly formed by a backing plate and a printing plate rmlyadhered thereto generally by means of a separate adhesive. The plaJtesupport functions to position the backing plate so that the printingplate may be separated therefrom by a power ydriven member without thenecessity for heating the parts or causing damage thereto. A bladesupport is movably mounted on the housing for movement along an axisparallel to the printing plate assembly in its support position andgenerally normal to the plate support. Mounted on the blade support at aminor angle relative to the axis of movement of the blade support and ingeneral alignment with the plate support is a blade which reciprocatesrelative to the plate support for insertion into the interface of thebacking and printing plates. Power means are mounted on the housing andengaged with the blade support for moving the blade relative to theplate support to separate the backing plate from the printing plate byshearing the joint made by the adhesive without damage to these parts.

ICC

The plate support preferably includes a saddle register disc with anarcuate groove of wedge-shaped cross-section therein for firmly grippingand supporting the backing plate in a position extending normally to thedisc. Desirably, the disc is rotatably mounted to permit loading in oneposition and rotation to the operative position, and may be providedwith a series of grooves using arcs of different radii to accommodatebacking plates of varying radii arranged ina circle. In the latterinstance, the blades would be interchanged to provide different radii ofcurvature, conveniently by a turret mounting arrangement.

To support the printing plate assembly more rigidly and particularlywhen the printing plate assembly is relatively long, the plate supportalso desirably includes an adjustable member to give additionalhorizontal support to the backing plate intermediate its length. In oneembodiment, the adjustable member may be a bolt that is mounted on thehousing and adapted to abut 4against the rear of the backing plate byadjustment of its length by suitable fasteners so that the backing plateis prevented from moving away from the pressure applied by the bladewhen the parts are being separated.

Although the blade may be mounted on the blade support at an angledeviating about 0.5 to about 30.0 degrees from the axis of movement ofthe blade support, an angle of deviation about 0.5 to 10.0 degrees hasbeen found to be most efficient. The blade has Ia body portion with anarcuate cross section, and a curved wedge-shaped portion at the free endthereof with a knife edge at its lower periphery. The shape of the bladeand the angle of inclination to the axis of movement combine to providean effective means for separating a backing plate from a printing platewithout damaging these parts.

The power means desirably utilizes a hydraulically driven piston mountedin a cylinder on the housing with a connecting rod engaged between thepiston and the blade support, and the hydraulic piston and cylinder maybe conventional in design and operated in the usual manner by either agas or liquid. In this manner, the apparatus may be operated with aminimum expenditure of time and labor t-o rapidly separate the printingplate from the backing plate without the time-consuming process ofheating the plate to weaken the adhesive and avoiding possible injury tothe plates by manual efforts.

In operation, the lower end of the plate assembly,

which is normally only the backing plate since it is of greater length,is inserted into the arcuate groove on the saddle disc so that it isheld in a position extending normally thereto. The disc is then rotatedso that the interface between the backing plate and the printing plate`is aligned with the blade and the adjustable member is positioned sothat it abuts against the rear of the backing plate and holds theseparts in the desired location. The

, hydraulic piston is then oper-ated in the usual manner so that theknife edge of the blade enters the interface between the plates in orderto shear the adhesive therebetween. As the knife edge proceeds furtherbetween the interface of the plates, the wedge shape of the bladeportion commences to push the printing plate away from the backing plateso that only a minimum of friction producing contact area is maintainedbetween the moving parts. The angle of the blade to the vertical and thewedgeshaped portion of the blade combine to move the printing plate awayfrom the backing plate with a minimum amount of friction by keeping thecontact area between `the parts to a minimum.

Referring now in detail to the attached drawing, the printing platedelaminating apparatus has a housing generally designated by the numeral10 'with a rectangular base plate 12 supporting a similar rectangulartop plate 14 by means of four spaced support columns f6 mounted onblocks 13 rigidly connected to the base plate 12 and top plate 14adjacent each of the corners thereof. Attached to the upper side of thebase plate 12 and the underside of the top plate 79 respectively areupper and lower mounting plates 20 and 22 which rigidly support theupper and lower ends of two spaced vertical guide rods 24.

Slidably mounted for vertical movement on the rods 24 is a cross bar 26which has cylindrical bores 28 through which the rods 2t) extend with asmall clearance so that the cross bar 24 is movable from the uppermounting plate 26 toward the lower mounting plate 18 with a minimum ofhorizontal play or movement. Rigidly mounted on the top plate 14 is aconventional hydraulic cylinder 30 which is connected to a pair ofsupply lines 32 provid ing a liquid or gas in the usual manner toreciprocate a hydraulic piston (not shown) within the cylinder. Theshaft of the piston or a separate connecting rod 34 is disposed inapertures 36 and 38 in the top plate 14 and the upper mounting plate 22and rigidly joins the hydraulic piston (not shown) with the cross bar 24to provide vertical movement of the cross bar 24 in the desireddirection on the rods 20 as suitable hydraulic pressure is applied inthe hydraulic cylinder 30 through either of the supply lines 32.

Attached to the underside of the cross bar 26 is a blade holder 50 whichsupports a blade, generally designated by the numeral 52, with an upperbody portion 54 of arcuate cross section and a wedge-shaped portion 56of arcuate cross section with a knife edge 58 at its lower periphery.The blade 52 is mounted so that it is at a minor angle a of aboutdegrees to the vertical or axis of movement of the blade support asillustrated, for facile delaminating of the printing plate assembly in amanner to be described hereinafter.

Rotatably supported on the lower mounting plate by the shaft 68 is aturntable or saddle register disc 70 having a circular groove 72 ofwedge-shaped cross section therein that receives and firmly supports thewedgeshaped lower end of a curved saddle or backing plate 74 in avertical position. 1t can be appreciated that the wedge-shapedconfiguration of lthe groove 72 will accommodate backing plates havinglower edge portions of varying angles and conguration since the taperingfront wall will provide wedging action against the vertical rear wall.The backing plate 74 supports a correspondingly curved face or printingplate 76 by means of an adhesive sheet or layer 78 at the interface ofthe plates 74 and 76 as illustrated in FlGURE 5. To limit horizontalmovement of the plates 74 and 76, a bolt 80 is mounted on a bracket 82attached to the two rear columns 16 and adjusted by the nuts $4 to abutagainst the rear of the backing plate 74. As will be appreciated, theradius of the arcs for the printing plate, the blade and the disc grooveshould be substantially equal to obtain optimum operation.

In order to delaminate the printing plate 76 from the backing plate 74,the hydraulic cylinder is actuated to move the cross bar 26, bladeholder 50 and blade 52 vertically downwardly on rods 24 so that theknife edge 58 and wedge portion 54 of the blade 52 come in contact withthe interface between the backing plate 74 and the printing plate 76with sufficient force to shear the joint made by the adhesive film 78.The conguration of the blade 52 ensures that the lowest portion of theknife edge 58 first enters the interface between the plates 74 and 76 onthe initial separation, and thereafter, the wedgeshaped portion 56 beingdriven between the plates effects further separation. As describedhereinbefore, the blade 52 is curved to form an arc corresponding to thearcuate interfaces between the plates 74 and 76 so that the force of theknife edge 58 is applied uniformly therebetween. During the descent ofthe blade as illustrated in FIGURE 4, the action of the wedge-shapedblade portion with its angle of deviation from the axis of movement atthe interface between the saddle 74 and the printing plate 75 moves theprinting plate 76 outwardly from the saddle 74. In this fashion,friction between the printing plate 76 and the blade 52 is minimized andthe parts are readily separated without damage thereto.

Thus, it can be seen that the present invention provides a novel andhighly effective apparatus for rapidly separating a printing plate froma backing plate with relatively small expenditures of time and labor.The delaminating apparatus separates the plates without causing damagethereto, is relatively simply in operation, and is relativelyinexpensive to manufacture. Moreover, backing plates of varying sizesand angles or contours may be received and supported firmly with aminimum of redesign of parts.

Having thus described the invention, we claim:

1. Apparatus for delaminating a printing plate assembly comprising: ahousing; a plate support on said housing having means for supporting, ina position normal thereto, one end portion of a printing plate assemblyformed by a backing plate and a printing plate firmly adhered thereto; ablade support movably mounted on said housing for movement along an axisparallel to said supported position and generally normal to said platesupport; a blade mounted on said blade support at a minor angle relativeto said axis of movement of said blade support and in general alignmentwith said plate support for reciprocal movement relative to said platesupport for insertion into the interface of the printing plates; andpower means mounted on said housing and engaged with said blade supportfor moving said blade relative to said plate support for separating thebacking plate from the printing plate.

2. The delaminating apparatus of claim 1 wherein said plate supportincludes a base support with an arcuate groove of Wedge-shaped crosssection therein for holding the printing plate assembly normal to saidbase support.

3. The delaminating apparatus of claim 1 wherein said plate support hasan adjustable member for supporting the printing plate assemblyintermediate its length to limit horizontal movement thereof.

4. The delaminating apparatus of claim 1 wherein said blade is mountedon said blade support at an angle deviating about 0.5 to about 10.0degrees from the axis of movement of said blade support.

5. The delaminating apparatus of claim 1 wherein said blade has a bodyportion of arcuate cross section and a wedge-shaped portion at the freeend thereof having a knife edge at its lower periphery.

6. The delaminating apparatus of claim 1 wherein said plate support isrotatably mounted on said housing.

7. Apparatus for delaminating a printing plate assembly comprising: ahousing; a plate support on said housmg includes a support base with anarcuate groove of wedge-shaped cross section therein for supporting in aposition normal thereto one end portion of a printing plate assemblyformed by a backing plate and a printing plate rmly adhered thereto; ablade support movably mounted on said housing for movement along an axisparallel to said supported position and generally normal to said platesupport; a blade mounted on said blade support at a minor angle relativeto said axis of movement of said blade support and in general alignmentwith said plate support for reciprocal movement relative to said platesupport for insertion into the interface of the backing and printingplates, said bllade having a body portion of arcuate cross section and awedge-shaped portion at the free end thereof having a knife edge at itslower periphery; and power means mounted on said housing and engagedwith said blade support for moving said blade relative to said platesupport for separating the backing plate from the printing plate.

8. The delaminating apparatus of claim 7 wherein said plate support hasan adjustable member for supporting the printing plate assemblyintermediate its length to limit References Cited horizontal movementthereof. i UNITED STATES PATENTS 9. The delammatmg apparatus of claim 7wherein sald blade is mounted on said blade support at an angle deviat-219931524 7/1961 Schuble 8:5487 X ing about 0.5 to about 10.0 degreesfrom the axis of 5 351521504 M1964 Brown 29427 X movement of said bladesupport. I 10. The delaminating apparatus of claim 7 wherein OTHELL MSIMPSON P' mary Examme said plate support is rotatably mounted on saidhousing. I. C. PETERS, Assistant Examiner.

1. APPARATUS FOR DELAMINATING A PRINTING PLATE ASSEMBLY COMPRISING: A HOUSING; A PLATE SUPPORT ON SAID HOUSING HAVING MEANS FOR SUPPORTING, IN A POSITION NORMAL THERETO, ONE END PORTION OF A PRINTING PLATE ASSEMBLY FORMED BY A BACKING PLATE AND A PRINTING PLATE FIRMLY ADHERED THERETO; A BLADE SUPPORT MOVABLY MOUNTED ON SAID HOUSING FOR MOVEMENT ALONG AN AXIS PARALLEL TO SAID SUPPORTED POSITION AND GENERALLY NORMAL TO SAID PLATE SUPPORT; A BLADE MOUNTED ON SAID BLADE SUPPORT AT A MINOR ANGLE RELATIVE TO SAID AXIS OF MOVEMENT OF SAID BLADE SUPPORT AND IN GENERAL ALIGNMENT WITH SAID PLATE SUPPORT FOR RECIPROCAL MOVEMENT REALTIVE TO SAID PLATE SUPPORT FOR INSERTION INTO THE INTERFACE OF THE PRINTING PLATES; AND POWER MENAS MOUNTED ON SAID HOUSING AND ENGAGED WITH SAID BLADE SUPPORT FOR MOVING SAID BLADE RELATIVE TO SAID PLATE SUPPORT FOR SEPARATING THE BACKING PLATE FROM THE PRINTING PLATE. 